Factors affecting survival of tree seedlings in North Queensland rainforests

摘要: Seedlings of six species rainforest trees with widely constrasting ecology and seed morphology were transplanted at 3 weeks age into tree-fall gaps the shaded understoreys two sites (Curtain Fig Lamins Hill) on Atherton Tableland, North Queensland, Australia. In each forest habitat, half seedlings protected from vertebrates by means wire cages, survival was monitored over 16 months. The main objective to estimate extent which independent variables (forest, protection vertebrates, species) contribute explaining differences among seedlings. Significant existed in mortality species, whether caged or uncaged. unprotected suffered greater (i.e. averaged all forests, > 75%), compared (mortality < 40%). Seedling most survived better gaps, though effects varied significantly species. Survival Curtain than Hill, a pattern attributed partial deciduousness forest. Because only few uncaged months, we focussed examine role light habitats survival. Relationship between seedling increasing availability vary However across decreased linearly as photosynthetically active radiation (PAR) rose 0.48 2.0%, after an asymptote reached further increase (up 8% PAR) did not influence significantly. Overall, temporal, various environmental their interactions explained about 60% variations data, making greatest contributions.